Examples of ways to have fun with a portable terminal such as a mobile phone and a smartphone include taking a selfie. Specifically, many portable terminals include a camera mounted thereon, and are capable of displaying, on a screen of a display in real time, an image picked up by the camera. Accordingly, a user can easily take an image of his/her face with a desired expression while checking his/her face with the screen of the display.
The camera is usually located at a position away from the position of the screen of the display. Therefore, the line of sight of the user in an image of the user's face taken by the user while viewing the screen of the display is slightly displaced.
A technology that modifies line-of-sight displacement of the user as an object by correction has been known (see, for example, Patent Document 2). In this technology disclosed in Patent Document 2, the amount of line-of-sight displacement is calculated on the basis of the amount of displacement between the center of the black eye of the user calculated from a registered looking-at-camera image and the center of the black eye in an image obtained by modifying the display position of the face in the face images of the user picked up by an upper camera and a lower camera, in a camera phone. On the basis of the amount of line-of-sight displacement, an image in which the line of sight is modified so that the user looks at the camera is generated.
Patent Document 1: Japanese Patent Application Laid-open No. 2012-114557 (paragraph [0051])